President Obama will give his farewell address to the nation in prime time on Tuesday, at 9 p.m. ET. White House aides say the speech is coming together, but here's what we know so far:

'His intention is to motivate'"It’s not a victory lap speech," said Valerie Jarrett, one of Obama's longest-serving aides. “His intention is to motivate people to want to get involved and fight for their democracy. You can’t take it for granted. You have to work hard at it. And it’s not easy and you have to be vigilant and determined."

"The running thread through my career has been the notion that when ordinary people get involved, get engaged, and come together in collective effort, things change for the better," Obama said in a Saturday radio address previewing the speech.

Sweet home, ChicagoThe McCormick Place convention center, the largest in North America, will be the venue. It's less than four miles from Grant Park, the site of Obama's 2008 victory speech. White House Communications Director Jen Psaki said he decided months ago that he would break with past practice and do his farewell speech outside of Washington. "Chicago was a natural place," she said.

Cold weather, hot ticketsAll the free tickets to the event have been distributed. People stood in zero-degree weather outside McCormick Place for hours Saturday morning for a ticket. By noon, tickets were being offered on Craigslist for $5,000, according to the Chicago Sun-Times.

He's still writing itWhite House press secretary Josh Earnest said Obama is still working on the speech, writing out parts of it longhand, dictating passages to speechwriters and then revising. He said it would be "shorter and much different in style" than a State of the Union Address.

"The president's committed to delivering a forward-looking speech that will examine briefly the significant progress that our country has made in the last eight years," Earnest said Monday. "But it will take a closer look at — and spend more time talking about — what the president believes is necessary for us to confront the challenges that lie ahead."

It's Obama's last trip as presidentEarnest said he expected the Chicago trip to be Obama's last trip outside Washington as president.

"I think it is likely to be his last Air Force One flight," Earnest said. Though he quickly clarified it wouldn't be his last trip on the plane. "It is obviously tradition for the former president to take one last flight aboard the presidential aircraft at the conclusion of the inauguration."

President Obama will say farewell Tuesday night to a nation he helped transform during his eight years in the White House.

Riding high in the polls but just days away from handing over the reins to a Manhattan mogul who has vowed to dismantle much of his legacy, Obama has chosen to make his final address as commander-in-chief in the city where he launched his unlikely and boundary-breaking political career — Chicago.

There Obama, who won the White House for the first time in 2008 on the message of "hope and change," will tell the supporters who have been with him from the start to take heart and not despair as he lays out what White House spokesman Josh Earnest is calling a "forward-looking" vision for America.

"America is a story told not minute to minute, but generation to generation," Obama wrote in a Facebook post advancing the speech, which he wrote himself. "We've made America a better, stronger place for the generations that will follow. We've run our leg in a long relay of progress, knowing that our work will always be unfinished. And we've reaffirmed the belief that we can make a difference with our own hands, in our own time."

For Obama, the address before a hometown crowd will cap a long goodbye during which he's reminded Americans where the nation was back in 2008, when the economy was in free fall and the country was mired in two unpopular wars — and how far the country has come since then.

Obama is likely to buttress his case with a battery of statistics as he touts the accomplishments of his two terms, which among other things includes a record 75 straight months of job growth, more than 15 million new jobs, a long-awaited rise in hourly wages — and the removal of Osama Bin Laden as a threat to America.

And, Earnest said, Obama will talk about "fairness and justices" and "the challenges that lie ahead."

"I can tell you, in general, that the President is committed to delivering a forward-looking speech that will examine briefly the significant progress that our country has made in the last eight years," he told reporters during a briefing on Monday. "But it will take a closer look and he'll spend more time talking about what the President believes is necessary for us to confront the challenges that lie ahead."

The Obamas have welcomed the Trumps to the White House, stressed national unity and chosen to focus on the smooth transition of power.

First Lady Michelle Obama, who like her husband remains a widely popular public figure, had tears in her eyes last week as she delivered a stirring goodbye speech.

"Being your first lady has been the greatest honor of my life," she said. "And I hope I made you proud."

Obama will deliver his speech at McCormick Place, which sits on the city's lakefront and is the largest convention center in North America. Some 14,000 people are expected to attend, the Chicago Tribune reported.